This invention relates to a novel electrical switch suitable for use as a window regulator switch, sunroof switch, or the like. It provides protection for these and other devices against a current overload (overcurrent) from excess currents, current surges, short circuits and the like.
For the protection of direct-off type switches from overcurrents, it is a common practice to employ a PCB pattern fuse or a built-in overcurrent protective device. For the protection of bus bar type switches, it is known to use a movable electrical contact, in which the melting of a resin member supporting or restraining the electrical contact causes an OFF fault. For the overcurrent protection of microswitches, the prior art has available only a PCB pattern fuse or a built-in overcurrent protective device.
PCB pattern fuses, however, are not completely reliable. Pattern width control during manufacture is so difficult to achieve that large variations in functional quality and reliability are inevitable. On the other hand, overcurrent protective devices are expensive and add to the bulk of switches.